The Collaborative International Dictionary of English v.0.48:

Crudle \Cru"dle\ (-d'l), v. i.
   See Cruddle.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Curdle \Cur"dle\ (k[^u]r"d'l), v. i. [From Curd.] [Sometimes
   written crudle and cruddle.]
   1. To change into curd; to coagulate; as, rennet causes milk
      to curdle. --Thomson.
      [1913 Webster]

   2. To thicken; to congeal.
      [1913 Webster]

            Then Mary could feel her heart's blood curdle cold.
                                                  --Southey.
      [1913 Webster]